Ameliorative effects of Juniperus rigida fruit on oxazolone- and 2,4-dinitrochlorobenzene-induced atopic dermatitis in mice

The fruits of Juniperus rigida have been used in Korean traditional medicine for the treatment of inflammatory diseases in humans such as rheumatoid arthritis. This study aimed to investigate the anti-atopic properties of J. rigida fruit in in vivo murine atopic dermatitis (AD) models. BALB/c mouse ears ad SKH-1 hairless mice stimulated with oxazolone (4 weeks) and DNCB (3 weeks), respectively, were treated with the 1% Juniperus rigida fruit EtOH extract (JFE). The JFE improved AD symptoms in both oxazolone- and DNCB-induced AD mice by accelerating skin barrier recovery function and suppressing the overproduction of serum immunoglobulin E (IgE) and interleukin 4 (IL-4). The JFE was found to contain isoscutellarein-7-O-β-xylopyranoside, cupressuflavone, podocarpusflavone A, and hinokiflavone as major components based on phytochemical analysis. Eight flavonoids were isolated from JFE, and of those, cupressuflavone and isoscutellarein-7-O-β-xylopyranoside strongly down-regulated IL-4 expression and β-hexosaminidase release in RBL-2H3 cells. Therapeutic attempts with J. rigida fruit and its active components might be useful in treating AD and related skin inflammatory diseases. [Display omitted]